System, apparatus and method for sensing automation picking and stacking

ABSTRACT

An apparatus for picking a product, including: a control circuit; at least one vacuum cup arranged to adhere, with negative pressure and at a first location, at least one sheet of material to the at least one vacuum cup; and at least one sensor to monitor an area proximate the at least one vacuum cup and transmit at least one signal regarding a presence of at least one sheet of material in the area. The apparatus is arranged to displace to a second location. The control circuit is arranged to determine, responsive to the at least one signal, the at least one sheet of material is not present in the area and generate an error signal indicating that the at least one sheet of material is not present in the area.

TECHNICAL FIELD

The present disclosure relates to a system, apparatus and method forsensing automation picking and stacking. In particular, the presentdisclosure relates to sensors to determine if material is picked byvacuum cups for stacking.

BACKGROUND

Known automated systems for picking and stacking material, such as printmedia, use a vacuum cup to pick the material and then displace the cupand media to stack the material in a different location. However, attimes the cup fails to pick up the required material or the requiredmaterial is dropped during transit to the stacking location. As aresult, the stacked material is incomplete and unsuitable for use. Theknown systems do not have a means for determining that stacked materialis missing material that failed to be transported to the stackinglocation.

SUMMARY

According to aspects illustrated herein, there is provided an apparatusfor picking a product, including: a control circuit; at least one vacuumcup arranged to create negative pressure and adhere, with the negativepressure and at a first location, the at least one sheet of material tothe at least one vacuum cup; and at least one sensor configured tomonitor an area proximate the at least one vacuum cup and transmit atleast one signal regarding a presence of at least one sheet of materialin the area. The apparatus is arranged to displace to a second location.The at least one sensor is configured to transmit the at least onesignal when the at least one sheet of material is not detected in thearea or the at least one sheet of material is detected in the area. Thecontrol circuit is arranged to determine, responsive to the at least onesignal, the at least one sheet of material is not present in the areaand generate an error signal indicating that the at least one sheet ofmaterial is not present in the area.

According to aspects illustrated herein, there is provided a method ofsensing material during a picking and stacking process, including:displacing, using a robotic arm, at least one apparatus such that atleast one vacuum cup for the at least one apparatus is aligned with atleast one sheet of material in a first direction; creating, using atleast one vacuum pump, negative pressure with the at least one vacuumcup; adhering, with the negative pressure, the at least one sheet ofmaterial to the at least one vacuum cup; displacing, using the roboticarm, the apparatus to a second location; monitoring, using at least onesensor, an area proximate the at least one vacuum cup; detecting, usingthe at least one sensor, that the at least one sheet of material is notin the area; transmitting, using the at least one sensor, at least onesignal to a control circuit, the at least one signal indicating that theat least one sensor has not detected the at least one sheet in the area;and generating, using the control circuit and in response to the atleast one signal, an error signal indicating that the at least one sheetof material is not present in the area.

According to aspects illustrated herein, there is provided a system forpicking and stacking a product, including: a robotic arm; and at leastone apparatus connected to the robotic arm. The at least one apparatusincludes: a control circuit; at least one vacuum cup arranged to createnegative pressure and adhere, with the negative pressure and at a firstlocation, the plurality of sheets of material to the at least one vacuumcup; at least one sensor configured to monitor an area proximate the atleast one vacuum cup and transmit at least one signal when a sheet ofmaterial, included in a plurality of sheets of material, is detected inthe area or a sheet of material, included in a plurality of sheets ofmaterial, is not detected in the area. The robotic arm and the apparatusare arranged to displace to a second location. The plurality of sheetsof material is arranged in a sequence. The control circuit is configuredto: determine, using the at least one signal, that the sheet of materialis not present in the area at the second location; determine a positionof the sheet of material within the sequence; and generate an errorsignal indicating that the sheet of material is not present in thesecond location and the position of the sheet in the sequence.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments are disclosed, by way of example only, withreference to the accompanying schematic drawings in which correspondingreference symbols indicate corresponding parts, in which:

FIG. 1 is a top perspective view of a system including apparatus forpicking and stacking a product;

FIG. 2 is a top view of the system of FIG. 1;

FIG. 3 is a detail of an apparatus in FIG. 1;

FIG. 4 is a schematic diagram of a control circuit for the apparatus inFIG. 3;

FIGS. 5A and 5B are respective block diagrams of the system in FIG. 1showing one apparatus; and,

FIG. 6 is a flow chart illustrating operation of the control circuit ofFIG. 4.

DETAILED DESCRIPTION

Moreover, although any methods, devices or materials similar orequivalent to those described herein can be used in the practice ortesting of these embodiments, some embodiments of methods, devices, andmaterials are now described.

FIG. 1 is a top perspective view of a system including apparatus 100 forpicking and stacking a product.

FIG. 2 is a top view of the system of FIG. 1.

FIG. 3 is a detail of an apparatus in FIG. 1.

FIG. 4 is a schematic diagram of a control circuit for the apparatus inFIG. 3. The following should be viewed in light of FIGS. 1 through 4.Apparatus 100 for picking a product includes at least one vacuum cup 102and at least one sensor 104. Cup or cups 102 are arranged to createnegative pressure. Sensor or sensors 104 are configured to monitor area106 proximate cup or cups 102 and transmit at least one signal 108regarding a presence of at least one sheet S of material M in area 106.For example, signal 108 is transmitted when at least one sheet S ispresent in area 106, or signal 108 is transmitted when at least onesheet S is not present in area 106. Unless stated otherwise, thediscussion that follows is directed to a plurality of cups 102 for eachapparatus 100 and a plurality of sensors 104 for each apparatus 100.However, it should be understood that the discussion is applicable to anapparatus 100 having one or both of a single cup 102 and a single sensor104.

Apparatus 100 includes control circuit 110 arranged to determine,responsive to at least one signal 108, at least one sheet of material Sis not present in area 106, and generate error signal 111 indicatingthat at least one sheet of material S is not present in area 106.

FIGS. 5A and 5B are respective block diagrams of system 200 in FIG. 1showing one apparatus 100. The following should be viewed in light ofFIGS. 1 through 5B. Apparatus 100 includes at least one port 112arranged to be connected to at least one vacuum pump 202. For example,each cup 102 has a respective port 112 connected to a respective pump202. Vacuum pumps 202 are arranged to generate negative pressures atcups 102. By “negative pressure” we mean a pressure less than theambient air pressure surrounding cup 102. In an example embodiment,system 200 includes robotic arm 204 to which one or more apparatuses 100are connected. In an example embodiment, arm 204 is rotatable about axisAR in circumferential directions CD1 and CD2. In an example embodiment,arm 204 is displaceable parallel to axis AR (in directions AD1 and AD2out of and into the sheet, respectively).

As shown in FIG. 5A, arm. 204 is controllable to rotate in direction CD1to position apparatus 100A at position L1 above sheet S1 in directionAD1. Vacuum pumps 202A and 202B are arranged to generate negativepressure at cups 102A and 102B, respectively. The negative pressure isarranged to draw sheet S1 toward cups 102A and 102B in direction AD1 andadhere sheet S1 to cups 102A and 102B. Sensors 104A and 104B areconfigured to determine that sheet S1 has not adhered to cups 102A and102B, that is, sheet S1 is not in area 106. Thus, apparatus 100A detectsand reports a failed picking operation for sheet S1.

As shown in FIG. 5B, arm 204 is controllable to rotate from position L1in direction CD1 to position sheet S1 over stack ST in direction AD1.The negative pressure is released from apparatus 100 so that sheet S1falls in direction AD2 onto stack ST. During the rotation of arm 204 andsheet S1 in direction CD1, sheet S1 can become disconnected from cups102A and 102B and apparatus 100A. In an example embodiment, sensors 104Aand 104B are configured to determine that sheet S1 has disengaged fromcups 102 (is not in area 106) during displacement to stack ST.

System 200, including multiple apparatuses 100 is shown in FIGS. 1 and2. In the example of FIGS. 1 and 2, system 200 includes threeapparatuses 100 and a plurality of sheets S, for example, each apparatus100 is arranged to pick up a respective sheet S by adhering therespective sheet with negative pressure at the respective cups 102.Although three apparatuses 100 are shown in FIGS. 1 and 2, it should beunderstood that other numbers of apparatuses 100 can be used in system200 and that system 200 is not limited to a particular number ofapparatuses 100.

Respective sensors 104 for each apparatus 100 are configured to transmitrespective signals 108 to control circuit 110 when: a sheet S,associated with the apparatus, is not detected in area 106 during apickup operation; or when a sheet S is not detected in area 106 during astacking operation. Control circuit 110 is arranged to generate, inresponse to signal 108, error signal 111.

In an example embodiment, for configurations of apparatus 100 includinga plurality of sensors 104, apparatus 100 is configured to generatesignal 111 if only one of the sensors 104 in the plurality of sensors104 determines that a sheet S is not within area 106. In the example ofFIG. 4, circuit 100 includes NAND gate 114. If the inputs to gate 114(from sensors 104) on lines 108 are not all the same, the NAND gateoutputs a low signal, which is inverted to a high signal on line 116.Lines 118 carry signals from sensors 104 to Input/Output (I/O) port 120.In response to a high signal on line 116, port 120 transmits errorsignal 111. Data from signals 118 is transmitted on line(s) 122.

In an example embodiment, control circuit 110 includes processor 124.For a system 200 including multiple apparatuses 100, the respectivesheets S are arranged in a sequence. For example, sheet S2 follows sheetS1 and sheet S3 follows sheet S2 in a stacking sequence. As furtherdescribed below, stacking at location ST typically involves multipleiterations of picking sheets S, displacing the sheets to location ST,and releasing the sheets at location ST. Thus, the sequence can includesmultiple repetitions of the S1 through S3 sequence. As noted above,sensors 104 are configured to transmit signal or signals 108 to controlcircuit 110 regarding presence of the respective sheets S in respectiveareas 106. In response to signal or signals 108 and 118, the controlcircuit, for example processor 124, is configured to determine aposition, in the sequence, of the sheet or sheets not detected in area106. Note that the detection of the position can be accomplished foronly a single sheet S not detected in area 106 or for multiple sheets Snot detected in areas 106. For example, if a stack requires fouriterations of the S1 to S3 sequence for a total of 12 sheets in thestack, and the middle sheet in the third iteration (eighth sheet in thestack) is not detected, processor outputs signal 126 identifying theeighth sheet as being missing in the stack. For example, if a stackrequires four iterations of the S1 to S3 sequence for a total of 12sheets in the stack, and the middle sheets in the second and thirditerations (fifth and eighth sheets in the stack) is not detected,processor outputs signal 126 identifying the fifth and eighth sheets asbeing missing in the stack.

Apparatus 100 is controllable such that negative pressure is created,simultaneously, by less than all of vacuum cups 102; or the negativepressure is created, simultaneously, by every vacuum cup 102. Forexample, negative pressure is created by cup 102A at a first point intime and at a second point in time, following the first point in time,negative pressure is created by cup 102B. The negative pressure at cup102A can be maintained or released when the negative pressure is createdby cup 102B.

FIG. 6 is a flow chart illustrating a method of picking and stacking aproduct. Although the method in FIG. 6 is depicted as a sequence ofnumbered steps for clarity, no order should be inferred from thenumbering unless explicitly stated. The method starts at Step 300. Step302 displaces, using a robotic arm, at least one apparatus such that atleast one vacuum cup for the at least one apparatus is aligned with atleast one sheet of material in a first direction. Step 304 creates,using at least one vacuum pump, negative pressure with the at least onevacuum cup. Step 306 adheres, with the negative pressure, the at leastone sheet of material to the at least one vacuum cup. Step 308displaces, using the robotic arm, the apparatus to a second location.Step 310 monitors, using at least one sensor, an area proximate the atleast one vacuum cup. Step 312 detects, using the at least one sensor,that the at least one sheet of material is not in the area. Step 314transmits, using the at least one sensor, at least one signal to acontrol circuit, the at least one signal indicating that the at leastone sensor has not detected the at least one sheet in the area. Step 316generates, using a control circuit and in response to the at least onesignal, an error signal indicating that the at least one sheet ofmaterial is not present in the area.

In an example embodiment, the at least one sensor includes a pluralityof sensors and detecting, using the at least one sensor, that the atleast one sheet of material is not in the area includes detecting, withless than all of the sensors included in the plurality of sensors, thatthe at least one sheet of material is not in the area.

In an example embodiment, the at least one sensor includes a pluralityof sensors and detecting, using the at least one sensor, that the atleast one sheet of material is not in the area

In an example embodiment, the at least one sheet of material includes aplurality of sheets of material arranged in a sequence and step 318determines, using the control circuit and the at least one signal, aposition in the sequence for only one single sheet of material, includedin the at least one sheet of material, not detected in the area.Further, generating the error signal includes generating the errorsignal including the position in the sequence.

In an example embodiment, the at least one sheet of material includes aplurality of sheets of material arranged in a sequence and step 320determines, using the control circuit and the at least one signal, aposition in the sequence for a sheet of material, included in the atleast one sheet of material, not detected in the area. Further,generating the error signal includes generating the error signalincluding the position in the sequence.

Advantageously, the method described above, apparatus 100 and system 200detect failed picking, transfer, and/or stacking operations; forexample: failing to pick up a sheet; losing a sheet during transfer tolocation ST; or losing a sheet at location ST. As a result, the problemsnoted above with respect to transferring and stacking material aregreatly reduced if not eliminated. Further, not only are failedoperations detected, but an additional level of information is provided,namely, identification of the lost sheet or sheets and the location ofthe lost sheet or sheets within a sequence of stacked sheets. Forexample, if there are fifty sheets in a finished stack and the twentiethsheet in the stack is lost, the method described above, apparatus 100and system 200 identify the sheet as being the twentieth sheet andprovides information, for example to an operator, so that the operatorcan manually replace the missing sheet. Thus, the problem is quicklyremedied using the already stacked sheets, avoiding the need to redo theentire stack.

It will be appreciated that various of the above-disclosed and otherfeatures and functions, or alternatives thereof may be desirablycombined into many other different systems or applications. Variouspresently unforeseen or unanticipated alternatives, modifications,variations, or improvements therein may be subsequently made by thoseskilled in the art which are also intended to be encompassed by thefollowing claims.

What is claimed is:
 1. An apparatus for picking a product, comprising: acontrol circuit; at least one vacuum cup arranged to: create negativepressure; and, adhere, with the negative pressure and at a firstlocation, at least one sheet of material to the at least one vacuum cup;and, at least one sensor configured to: monitor an area proximate the atleast one vacuum cup; and, transmit at least one signal regarding apresence of at least one sheet of material in the area, wherein: theapparatus is arranged to displace to a second location whilecontinuously monitoring, using the at least one sensor, the areaproximate the at least one vacuum cup; the at least one sensor isconfigured to transmit the at least one signal when: the at least onesheet of material is not detected in the area; or, the at least onesheet of material is detected in the area; and, the control circuit isarranged to: determine, responsive to the at least one signal, the atleast one sheet of material is not present in the area; and, generate anerror signal indicating that the at least one sheet of material is notpresent in the area; the at least one vacuum cup includes a plurality ofvacuum cups.
 2. The apparatus of claim 1, wherein: the at least onesheet of material includes a plurality of sheets of material; and, theat least one vacuum cup includes a plurality of vacuum cups arranged toadhere, with the negative pressure, the plurality of sheets of materialto the plurality of vacuum cups.
 3. The apparatus of claim 1, whereinthe at least one sensor includes a plurality of sensors configured totransmit the at least one signal when less than all of the sensorsincluded in the plurality of sensors: do not detect the at least onesheet of material in the area; or, detect the at least one sheet ofmaterial in the area.
 4. The apparatus of claim 1, wherein the at leastone sensor includes a plurality of sensors configured to transmit the atleast one signal when only one single sensor included in the pluralityof sensors: does not detect the at least one sheet of material in thearea; or, detects the at least one sheet of material in the area.
 5. Theapparatus of claim 1, wherein: the at least one sheet of materialincludes a plurality of sheets of material arranged in a sequence; and,when the control circuit determines that only one single sheet ofmaterial, included in the at least one sheet of material, is not presentin the area, the control circuit is configured to determine a positionof the only one single sheet of material within the sequence.
 6. Theapparatus of claim 1, wherein: the at least one sheet of materialincludes a plurality of sheets of material arranged in a sequence; and,when the control circuit determines that a first sheet of material,included in the at least one sheet of material, is not present in thearea, the control circuit is configured to determine a position of thefirst sheet of material within the sequence.
 7. The apparatus of claim1, wherein: the at least one vacuum cup includes a plurality of vacuumcups; and, the at least one sensor includes a plurality of sensors. 8.The apparatus for picking a product of claim 1 wherein the at least onesensor consists of a single sensor.
 9. The apparatus for picking aproduct of claim 1 wherein the at least one vacuum cup comprises atleast two vacuum cups and the at least one sensor comprises at least onesensor associated with each vacuum cup of the at least two vacuum cups.10. The apparatus for picking a product of claim 9 wherein each of theat least one sensors associated with each of the at least two vacuumcups are connected by the control circuit.
 11. The apparatus for pickinga product of claim 9 wherein the control circuit further comprises aNAND gate and each of the at least one sensors associated with each ofthe at least two vacuum cups are connected by the NAND gate.
 12. Amethod of sensing material during a picking and stacking process,comprising: displacing, using a robotic arm, at least one apparatus suchthat at least one vacuum cup for the at least one apparatus is alignedwith at least one sheet of material in a first direction; creating,using at least one vacuum pump, negative pressure with the at least onevacuum cup; adhering, with the negative pressure, the at least one sheetof material to the at least one vacuum cup; continuously monitoring,using at least one sensor, an area proximate the at least one vacuumcup; displacing, using the robotic arm, the apparatus to a secondlocation; detecting, using the at least one sensor, that the at leastone sheet of material is not in the area; transmitting, using the atleast one sensor, at least one signal to a control circuit, the at leastone signal indicating that the at least one sensor has not detected theat least one sheet in the area; and, generating, using the controlcircuit and in response to the at least one signal, an error signalindicating that the at least one sheet of material is not present in thearea, wherein the at least one sheet of material includes a plurality ofsheets of material arranged in a sequence, the method furthercomprising: determining, using the control circuit and the at least onesignal, a position in the sequence for a first sheet of material,included in the at least one sheet of material, not detected in thearea, wherein generating the error signal includes generating the errorsignal including the position in the sequence.
 13. The method of claim12, wherein: the at least one sensor includes a plurality of sensors;and, detecting, using the at least one sensor, that the at least onesheet of material is not in the area includes detecting, with less thanall of the sensors included in the plurality of sensors, that the atleast one sheet of material is not in the area.
 14. The method of claim12, wherein: the at least one sensor includes a plurality of sensors;and, detecting, using the at least one sensor, that the at least onesheet of material is not in the area includes detecting, with only onesingle sensor included in the plurality of sensors, that the at leastone sheet of material is not in the area.
 15. The method of claim 12,further comprising: determining, using the control circuit and the atleast one signal, a position in the sequence for only one single sheetof material, included in the at least one sheet of material, notdetected in the area, wherein generating the error signal includesgenerating the error signal including the position in the sequence. 16.The method of claim 12, wherein detecting, using the at least onesensor, that the at least one sheet of material is not in the area isperformed while adhering the at least one sheet of material to the atleast one vacuum cup, while displacing the apparatus to a secondlocation, and while stacking the at least one sheet of material.
 17. Asystem for picking and stacking a product, comprising: a robotic arm;and, at least one apparatus connected to the robotic arm, the at leastone apparatus including: a control circuit; at least one vacuum cuparranged to: create negative pressure; and, adhere, with the negativepressure and at a first location, a sheet of material of a plurality ofsheets of material to the at least one vacuum cup; at least one sensorconfigured to: monitor an area proximate the at least one vacuum cup;and, transmit at least one signal when: the sheet of material, includedin a plurality of sheets of material, is detected in the area; or, thesheet of material, included in a plurality of sheets of material, is notdetected in the area, wherein: the robotic arm and the apparatus arearranged to displace to a second location while continuously monitoring,using the at least one sensor, the area proximate the at least onevacuum cup; the plurality of sheets of material is arranged in asequence; and, the control circuit is configured to: determine, usingthe at least one signal, that the sheet of material of the plurality ofsheets of material is not present in the area at the second location;determine an intended position of the sheet of material within thesequence; and, generate an error signal indicating: that the sheet ofmaterial is not present in the second location; and, the intendedposition of the sheet in the sequence.
 18. The system for picking andstacking a product of claim 17 wherein the at least one vacuum cupcomprises at least two vacuum cups and the at least one sensor comprisesat least one sensor associated with each vacuum cup of the at least twovacuum cups.
 19. The system for picking and stacking a product of claim18 wherein each of the at least one sensors associated with each of theat least two vacuum cups are connected by the control circuit.
 20. Thesystem for picking and stacking a product of claim 18 wherein thecontrol circuit further comprises a NAND gate and each of the at leastone sensors associated with each of the at least two vacuum cups areconnected by the NAND gate.